02-13-13: Philipwu
my guess is ... when a transformer is used to split signal that enters from RCA connector into positive & negative phase for further "procresing" then the amp is fully balance.
I don't think we can say, based on the description at the Coincident site, whether or not the RCA inputs are converted into a balanced pair of signals. In fact, their statement that I quoted in my previous post could be taken to mean that the circuits are configured very differently depending on whether the rear panel switches are set to balanced or unbalanced.
... if a balance connector is added for convenience and subsequently, signal enter through this balance connection then get converted by transformer into SE circuit,i would guess it would not be full balance circuit, right?
Yes, but again there is no specific indication that that is how the circuit is designed.
The only meaningful clues, as I see it, are that the design is transformer coupled at both its inputs and its outputs, and that the only active device in between is a single-section triode. Which per my previous post probably means, at least arguably, that it is not "fully balanced" in the usual sense of that term. Although if the topology is such that a balanced signal pair is input to the tube via the grid and cathode circuits, as I described earlier, and the single-ended output from the plate is converted to balanced via the output transformer, the design could perhaps be considered as falling within a loose definition of "fully balanced."
Regards,
-- Al
